Cables containing many small diameter wires are often used in telephone communication systems that are typically installed underground. All such cables capable of being installed underground must be sealed against moisture and otherwise protected against the hostile environment. Not infrequently, due to line failure or routine maintenance, one or more cables must be joined, i.e., many wires within spliced together. Thus, entry into the cable systems and effective resealing is necessary.
Currently, there are a variety of insulating covers and protectors for electrical connections, cable splices, repair and the like. While effective in providing protection and a seal for the connections, installation of the known covers is relatively time-consuming, often requiring specialized tools and equipment which in an underground tunnel of limited space are difficult to handle and operate.
One such known protector employs a rigid outer shell that is installed around the splice area and filled with urethane or other hard resins. The splice area is totally and permanently encapsulated and is not readily reenterable.
Another known closure utilizes a rigid outer cover, but is filled with a petroleum jelly or other similar, very viscous material. For access to the splice area, this petroleum jelly must be removed, creating problems in removal, temporary storage or disposal.
Another commonly used protector is a heat-shrinkable sleeve. In addition to requiring special heating tools, there is the potential for deterioration of the integrity of the material due to overheating. Also, the available heat-shrinking materials for such applications are typically of high durometer to withstand the hostile environment, making re-entry as by slicing more difficult and limiting the flexibility of the spliced area.
While epoxy-type resins are known to be used for cable repair, they are disadvantageously limited by temperature. Such resins also have a tendency to crack under stress and often have poor adhesive properties for a seal to the cable.